As a result of the recent developments in medical techniques and the general medical care of hearts, a number of serious and mild cardiac diseases have been discovered and aided by the cardiac therapy.
However, mild cardiac patients, particularly mild cardiac sick children discovered at school by cardiac examination conducted nationwide are prevented from joining swimming training as being too severe an exercise, in some cases.
In conventional infant circulatory organ science, the reason that the mild cardiac infant cannot swim safely is based on the result of consideration of the energy consumption and the measured result of inspection of the electrocardiogram of the infants recorded on the ground. So far, there has been no electrode for recording the electrocardiogram during swimming. Therefore, the swimming restrictions are not based on the result of the inspection of the electrocardiogram during actual swimming.
However, the circulatory action during swimming is different from that during the exercises on the ground, and abnormal variations are observed during swimming, since accurate circulatory action of a pupil during swimming cannot be determined at present, safety of the mild cardiac sick pupil cannot be therefore confirmed. It is difficult to give approval of swimming to the mild cardiac sick pupil who has to be allowed to swim, based on the conventional inspection.
Then, it becomes necessary to prove that the pupil can safely swim by recording the electrocardiogram during actual swimming.
In order to record the electrocardiogram of the human body during swimming, it is necessary to detect ultrafine current induced on the skin of the human body during swimming by electrodes attached on the skin, and to lead said current to an electrocardiograph on the ground to measure the variation in the potential generated in the human body.
Since the electrodes attached on the skin of the living body are easily separated from the skin in the water, the electrodes may be bonded with adhesive or bonding agent on the skin in some cases. However, it is troublesome to bond the electrodes on the skin and it gives a load for an examinee. Even if the electrodes were bonded with adhesive on the skin, they can be separated from the skin during severe swimming exercise. Further, since the waterproofness of the electrodes may not be adequate, there is a drawback or a disadvantage that a good electrocardiogram cannot be obtained.